#include <iostream>
#include <vector>
#include <algorithm>
#define endl '\n'
#define int long long
#define pii pair<int, int>
using namespace std;

// 已知
int n;
// 未知

signed main()
{
    cin >> n;
    if (400 % n == 0)
    {
        cout << 400 / n << endl;
    }
    else
    {
        cout << -1;
    }
    return 0;
}